1. Technical Field of the Invention
The present invention relates to novel fragrance/perfume compositions comprising:
(a) from 11% to 60% by weight of a mixture of odoriferous materials,
(b) from 51% to 80% by weight of ethanol, and
(c) from 3% to 30% by weight of decamethyltetrasiloxane, with respect to the total weight of the composition.
2. Description of Background and/or Related and/or Prior Art
Fragrance compositions usually comprise a mixture of odoriferous materials which have a vapor pressure of less than atmosphere pressure at 25° C. and which are generally liquid at 25° C., but which are sometimes also solid, in a physiologically acceptable medium based on ethanol and optionally on water.
Ethanol is a good dissolving agent for perfuming ingredients and exhibits, in addition, the advantage of being inexpensive and of making possible the formulation of transparent compositions. On the other hand, it has the disadvantage of reacting chemically with nitrogen oxides in the atmosphere to form ozone and therefore constitutes a source of atmospheric pollution which it is desirable to avoid.
It is therefore usual to replace a portion of the ethanol with water. However, water and ethanol are not chemically inert and react with the compounds of the fragrances, producing, over time, olfactory changes of a detrimental nature and/or modifications in the appearance of the liquids (yellowing, browning). The chemical reactions responsible for this deterioration are mainly:                the formation of acetals, by condensation of ethanol with chemical compounds comprising an aldehyde functional group;        the saponification or hydrolysis of compounds comprising an ester functional group;        the oxidation of monoterpenes or sesquiterpenes present particularly in plant extracts; and        the oxidation of ethanol to acetaldehyde and then to acetaldehyde diethyl acetal (DEA), accompanied by the formation of acetic acid and then of ethyl acetate.        
In addition, water is not a good solvent for fragrances and reduces the solvating power of ethanol. Problems of cloudiness or of dissolution sometimes appear from the beginning of the formulation of the fragrances and necessitate a significant reduction in the level of fragrance. This results in more dilute fragrances, whereas the current trend is to produce fragrances which are instead strong and highly concentrated (more than 10% of perfuming materials).
The advantage in substituting, for the water present in fragrances, another starting material which is inert, which is volatile, which has good miscibility with ethanol and which makes it possible to dissolve large amounts of perfuming ingredients is thus apparent.